Selector



Jan. 30, 1934. H. M. FRIENDLY SELECTOR 3 Sheets-Sheet l Original Filed March l. 1920 @es Ch w @www S QN @N Jan. 30, 1934. H. MfFRxENDLY SELECTOR Original Filed March 1. 1920 3 Sheets-Sheet llllllllllll NQS .mmm

Jan. 30, 1934.

H. M, FRIENDLY 1,945,465

SELECTOR Original Filed March 1, 1920 3 Sheets-Sheet 3 B5 Mf/Mm FIT-big.

Patented Jan. 30, 1934 PATENT OFFICE SELECTOR Herbert M. Friendly, Chicago, Ill.; Milton S. Friendly and Central Republic Trust Company, executors of said Herbert M. Friendly, deceased Application March 1, 1920, Serial No. 362,321 Renewed August 31, 1928 54 Claims. (Cl. 179-27) The present invention is a continuation in part of my pending application Serial No. 171,637, led May 29, 1917.

Figs. 1 and 2 in the present application show improvements in Figs. 26 and 1G respectively, of the parent case, the connections of which last named figures are described in the specification of the parent case.

My invention relates to what are generally known as full automatic telephone systems, semiautomatic telephone systems and variations of such systems, including manual systems; the present invention necessitating novel departures from equipments heretofore known, in attaining the novel objects, however, retaining certain operative functions which are known.

Referring to the accompanying schematic drawings:

Fig. 1 shows a calling automatic telephone leading to a lineswitch of well known type; the latter having access to a first selector, however, with the addition of a metering device operatedby a cam spring set designated C. S. which is adapted to function when all trunks of a level have been tested and found busy; the said meter registering the number of times of such occurrence;

Fig. 2 is the selector of the present invention, accessible from the selector in Fig. 1. The lines extending to the right hand edge of the sheet in Fig. l. are to be registered with those extending to the left hand edge of the sheet in Fig. 2; and

Fig. 3 is a receiving circuit at the traflic operators switchboard. The lines extending to the right hand edge of Fig. 2 are to be registered with those extending to the left hand edge of the sheet in Fig. 3.

The present invention contemplates the following and other novel objects:-

Heretofore, selectors having a directed primary movement and an automatic secondary testing movement have been limited to being able to select an idle trunk of a single trunk group. In the present invention the selector is adapted to select and seize trunks in two independent, irrelevant groups in a single bank level alternatively. That is, one group in a level is adapted to be normally selected and the other group of the said level is adapted to be selected only provided a preliminary, or group-preparing, operation of the selector ensues due to the agency controlling the selector being operated to cause the said preliminary or group-preparing operation in the selector.

The selector of the present invention has two private wipers, one being an auxiliary private wiper, there are two sets of auxiliary bank contacts adapted to be engaged by the auxiliary wiper as it passes over successive rotary positions of a level. Each said set of auxiliary bank contacts are tied to a common conductor in multiple relation respectively. In the exampled selector the sets of auxiliary bank contacts are shown alternatng. That is, the yrst, (excepting in the ninth level) third, fifth, etc., auxiliary bank contacts of a level connect to one common conductor while the second, fourth, sixth, etc., auxiliary bank contacts of the same level connect to a second common conductor. 0f course, the matter of alternate arrangement stated is not essential as the grouping may be in any order, nor is it essential to have all the levels divided into equal groups or to have all the levels arranged with two groups of trunks.

The common conductors lead to the resting and 'I5 working contacts respectively of the grounded armature of a relay in the selector. Thus only one said conductor will be grounded at a time by the said armature, the other conductor being free -from ground at the armature. Which conductor will be grounded and which will be free will depend upon whether the armature is normal or attracted.

The private wiper has the generally well known relation to the elements of the selector having to do with the rotation and cutting-in. However, upon the shaft of the selector attaining the second rotary position a relay will become actuated and cause the private wiper and the auxiliary wiper to be tied together. So if the auxiliary wiper encounters ground thereafter it is equivalent to the private wiper encountering busyground. Until the shaft of the selector attains the second rotary position the auxiliary wiper`A extends to the winding of theA relay upon which is the said grounded armature.

The first auxiliary bank contact of the ninth level is independently grounded. Soif the auxiliary wiper is caused to rotate-in at the ninth level, upo the auxiliary wiper encountering the said grounded bank contact the said relay controlling the grounded armature will be caused to actuate and lock; also causing the release magnet to energize and restore the selector shaft to normal, incidentally causing the relay which ties the private and auxiliary wipers to actuate and lock and so tie them.

The first digit series sent (being digit 9 in the exampled instance) has thus been obliterated due to the restoration of the selector shaft. Howously ungrounded arenow grounded. Thus, the

previously non-seizable trunks are now seizable,

. and vice versa.

It also follows that had some other digit than 9" been sent the trunk group now non-seizable would be seizable to the specific selector by automatic process forthwith at the termination of the digit. series.

From the foregoing general statements, and as will appear presently, the present invention provides for controllably gaining access to either of two groups on a level where all trunks of the level are subject'to test when-any trunk of the level is sought.

Other objects of the invention, and the invention'itself'will be clear from the following description thereof:

The illustrative application of the present invention chosen is its employment as a special second selector having the twofold object of protecting the system against erroneous calls when the calling party inadvertently introduces an impulse preliminary to manipulating the calling device in making a call and of diverting such vitiated calls to the "trafc operators switchboard.

This impulse so introduced has been termed a preliminary impulse. The impulse, unless provided against, will aifect the switches as a normal calling impulse and of course vitiate the call. 'Ihis preliminary impulse is usually introduced by falsely flashing the hookswitch when removing the receiver to initiate the call.

In practice it is usual to employ a single battery source, and this battery has one of its poles permanently grounded. Also it is usual to employ a single ground, the said battery and ground being multipled respectively to terminals of the elements adapted to each respectively. To simplify the drawings and description the battery and ground is shown as independent sources throughout wherever applied.

In the description, when a circuit is traced to a winding the opposite terminal of which is shown applied to grounded battery or to ground, the described circuit is to be considered as traced to ground through the winding and battery, or direct to ground as indicated. I

Assume that calling party at telephone P removes the receiver from the hookswitch to initiate avcall. The path between the line conductors 5 and 6 will be closed through the telephone P. Slow-releasing relay 7 will now energize and actuate over the circuit from its winding, con- I tacts 8 9, conductor 6, telephone P, conductor 5,

contacts 10-11, to supervisory ground. A second circuit can now be traced from supervisory ground, armature l2, working contact 13, pulldown winding 14 to open main battery, causing the lineswltch to plunge in and cause springs 15- 16, 17-18, 19-20 and 21-22 to engage respectively, all in a well known manner. a

A circuit can now be traced from the upper winding of relay A, resting contact 23, armature 24, conductor 25, contacts 19-20,k conductorv 5, telephone P, conductor 6, contacts 22-21, conductor 26, armature 27, resting contact 28,.lower winding of relay A, contact 29to grounded contact 30. Relay A will actuate and apply grounded armature 31 to working contact 32 and to the winding of slow releasing relay B, causing it to actua Grounded wcrkingconta'ct 3 3isapplied to amature 34 and to'conductor 35.

Winding 1'4 does not exert 'enough tractiveforce to disassociate contacts 8-9 and 10--11 but when cut-olf winding 36 is energized through 'a l contacts 16-15 and the grounded conductor`35 Y' the contacts 8-9 and 10-'11 are ldisassociaterl and lrelay 7 will retractits period thereafter, v winding 36 maintaining the lineswltch fully plungedin. L, l

'I'he bank contacts shown` on the right are 'the ilrst ones of the ten line and privatelevels, there being a plurality following. In fact it has been usual to have ten sets in each level of selector banks. Of course, `the 4number of levels, and 0 moreover, the number of bank contact sets in each level are not essential. a v

Assume that. after the stated and described f functioning, but before the calling party operates ture 31 to resting contacts 37-38, armatures 10| 39-40, working contact 4l, (relay B sustaining) winding of slow-releasing relay C to the vertical magnet, causing the vertical magnet to actuate, and also relay C to actuate and sustain for its period after the lapse of current. The 101 shaft carrying wipers 42, 43 and 44 will be stepped up one vertical position, said wipers registering in line with bank contacts 45, 46 and 47 respectively.`

Incidental to the ilrst oil normal movement of the shaft, contact sets 48-49 and 50-51 engage. These are referred to as oil-normal contacts and designated O.N. A circuit can now be traced from winding of shunted relay E', contacts 49-48, working contact 52, armature 53 113 to the grounded conductor 35, causing said E to actuate. Upon relay C deactuating a circuit can `be ltraced from the grounded conductor 35, armature53, resting contact 54, armature 55, working contact 56 to the rotary magnet (designated Rot.M.), causing it to actuate and drive the shaft one rotary step, wipers 42, 43 and 44 engaging bank contacts 45, 46 and 47 respectively. Incidental to the rotary magnet attracting, its auxiliary armature 57 is attracted from resting contact 58. At the time armature 53 retracted from working contact 52 a supplemental locking circuit for relay E existed by way of armature 57, resting contact 58, armature 59 and grounded working contact 60. It will be noted that the locking circuit to relay E opened at contacts 57-58, causing said E to deactuate. It will be noted that the winding of relay D was shortcircuited to ground from conductor 61, armature 59 to grounded working contact 60, while relay E was actuated, so no current from the winding of relay E can energize it (D) by way of armature 57 and resting contact 58, after relay C deactuates and before armature 57 attracts from l resting contact 5s. j 4C Bank contact 45l being ungrounded 4(due to being idle at other selectors having access to similar multipled bank contacts), a circuit path can be traced from the winding of relay E, cond tacts 49748,l armature 5,7, resting contact 58, conductor 61, winding of relay D, contacts 62-63 to the .grounded conductor 35, causing relay D to actuate, but due to the marginal adjustment of relay E, with reference to the resistance .of the 15 winding of relay D, it (relay E) will remain deactuated.

The circuit traced from telephone P to armatures 24 and 27 is now extended from armature 24 to working contact 64, conductor 65, wiper 43, bank contact 46, conductor 66, armature 201 (Fig. 2) resting contact 202 to the upper winding of relay A2, and from the lower winding thereof to resting contact 203, amature 204, conductor 205, bank contact 47, wiper 44, conductor 67, working contact 68 to armature 27. Relay A2 will actuate, applying grounded armature 206 to working contact 207 and to the winding of slow-releasing relay B2, causing it to actuate and apply grounded working contact 208 to armature 209 and working contact 210; armature 209 attaching to conductor 212. The said grounding of conductor 212, occurs before relay B (Fig. 1) deactuates resultant to relay D actuating, so the ground is communicated from said 212, bank contact 45, wiper 42, conductor 69, armature 70, working contact 71 leading to conductor 35, before ground has lapsed from said 35. Thus, relay D and the lineswitch winding 36 is sustained to ground on working contact 208 on relay B2 of Fig. 2 in lieu of to grounded working contact 33 on relay B of Fig. 1.

Should the calling party replace the receiver on the hookswitch and open the circuit path traced from the windings of relay A2, relay B2 will deactuate and remove ground from conductor 35, whereupon relay D will deactuate. A circuit will then ensue from the winding of the release magnet in Fig. 1 (designated RM.) contacts 51-50, resting contact 72, armatures 40-39, resting contacts 38-37 to grounded armature 31, causing the said release magnet to actuate and restore Fig. 1 to normal.

However, should the calling party in lieu of replacing the receiver on the hookswitch, vsend digit 1 from the calling device 73, effectuating one open impulse, relay A2 will deactuate and reactuate one time responsive thereto. Incident upon the deactuation of relay A2 armature 206 Will retract against resting contact 213, applying the ground thereon to resting contact 214, armatures 215-216, (relay B2 sustaining) working contact 217,. series winding of slow-releasing relay C2 to the winding of the vertical magnet (designated V.M.2), causing it to actuate one time.

The shaft carrying wipers 218, 219, 220 and 221 will be caused to step up so the said wipers will register in line with bank contacts 222, 223, 224 and 225 respectively of the said first level. Relay C2 will deactuate its period following the lapse of current applied through it to the vertical magnet.

Incidental to the shaft being stepped from its normal position the set of off-normal contacts (designated O.N.2) will be operated. Upon the actuation of relay C2 ground will be applied from conductor 212, armature 226, working contact 227 to conductor 228, contacts 229-230 to the winding of shunted relay E2, causing said E2 to actuate and lock to supplemental ground by Way of armature 231, resting contact 232, arma- Y ture 233 to working grounded contact 234.

Relay E2 can become unlocked only when the to actuate and rotate the wipers into engagement with the first set of bank contacts before set ductor 212, causing relay D2 to actuate. Relay E2 being m^rginally adjusted with reference to relay D2 will not actuate in series with said D2.

The circuit from telephone P heretofore traced to armatures 201 and 204 is now continued from armature 201 to working contact 241, conductor 242, wiper 220, bank contact 224, conductor 243 to upper winding of relay A3 and from the lower winding of relay A3, conductor 244, bank contact 225, wiper 221, conductor 245, working contact 246 to armature 204. Relay A3 will actuate, applying grounded armature 301 to working contacts 302 and 303. That is, ground is now applied to conductor 304, bank contact 222, wiper 218, conductor 247, armature 248, working contact 249 to conductor 212. Relay A3 actuates before slow-releasing relay B2 deactuates consequent upon relay D2 actuating, so there will be no lapse of ground to conductor 212 and therefore relay D2 will maintain actuated over the described path to grounded armature A3, in lieu of to the grounded armature 209 on relay B2, upon the deactuation of said B2.

Wiper 219 now engaging bank contact 223 has no operative function at this-juncture since common conductor 250 leading from the now disengaged contact 251 and lwhich attaches in multiple relation to said bank contact 223 and to the third, fifth, etc., contact following, can

complete no ground path. It is clear from the drawings the common conductor 250 and also the common conductor 252, are local to the specific selector, that is, have no conductive relation to other selectors having access to the same conductors from corresponding bank contacts.

The ground applied to contact 303, contacts 305-306 to lamp 307 causes it to glow, apprising the traid operatorA that a false call ensues. By manipulating key K3 and closing contacts 308-309 into engagement with contacts 310-311 respectively, the said operator will (through telephone set Q3) gain telephonie connection with conductors 243 and 244 and be therefore enabled to converse with the calling party and inform him of his calling error. Contacts 305-306 will disassociate incidental to the key K3 being manipulated, extinguishing the lamp 307.

Had the wiper 218 encountered busy ground I.

on bank contact 222, due to conductor 304 being grounded (because of it having been seized at some other selector accessible), when the armature 233 retracted the ground-short-path at the upper winding terminal of relay D2 will be maintained from conductor 238, resting contact 253, armature 248, conductor 247, wiper 218 to said grounded bank contact 222. Relay D2 cannot actuate since it thus has ground potential on both winding terminals, and relay `E2 will reactuate over the path including contacts 230-229, conductor 228, armature 231, resting contact. 232, conductor 238, resting contact 253, armature 248, conductor 247, wiper 218 to said grounded bank contact 222.

Relay B2 being- Incidental to the .wipers rotating from the first set of bank contacts, rotary off-normal con-- tacts (designated R. O. N. 2) engage. This applies ground to conductor 254 and to the winding of relay G2, causing it to actuate. Therefore, at the time wiper 219 engages the second position bank contact 255 a circuit can be tracedfrom grounded armature 256, resting contact 257, conductor 252, bank contact 255, wiper 219, ar-

' mature 258, working contact 259 to conductor 247, to which conductor attaches Wiper 218. Re-

gardless of the state of bank contact 260 (whether it is busy-grounded or not) the condition to con-y ductor 247 will be equivalent to wiper 218 encountering ground thereon as on bank contact 222, so the same re-functioning of relay E2, followed by the actuation of the rotary magnet to advance the wipers another step and unlock relay E2, will again ensue as when the grounded bank contact 222 was encountered. The conductor 250 being non-grounded, the third bank contact adapted to be engaged by wiper 219 can have no operative influence, so the state of third bank contact adapted to be engaged by wiper 218 will ,solely determine the functioning as in the case of wipers 218 and 219 engaging bank contacts 222 and 223 respectively. It is clear that this functioning will continue until all the bank contact positions are tested and rotated from if the contacts counting alternately from 222 have ground potential thereon. Of course, it will be understood that the said alternate bank positions correspond to trunks having the same switchboard as a destination as the one leading from the said first bank position of the level.

Assume that when the calling party was responded to by the traffic operator and during the connection, or after the'operator restores the key K3, the calling party replaces the receiver on the hookswitch. Relay A3 willl deactuate and thereby remove thev ground from conductor 304. Remembering that the winding of relay D (and the winding 36 of the lineswitch) are grounded from conductor 212 and that the Winding of relay D2 is also grounded to said 212, say relay 36, D and D2 will deactuate. The selector and lineswitch in Fig. 1 will restore as before described when ground was removed from conductor 35. Selector Fig. 2 will restore as followsz--Ground on armature 206 will be applied to resting contacts 213-214, armatures 215-216, resting contact 261, contacts 262--263 to the winding of the release magnet (designated R. M. 2), causing it to actuate and restore the selector Fig. 2 to normal.

Assume that in lieu of the calling party sending digit 1 from the calling device 73 was sent,

digit 0, the operation of Fig. 2 would be as before, only that the shaft would be stepped up to the 0 level where it would rotate-in (as before on the rst level), the wipers 218, 219. 220 and 221 engaging bank contacts 264, 265,266 and 267 respectively.

Assuming that no busy-ground exists on bank contact 264, the selector Fig. 2 will seize in the manner as before set forth, and the calling telephone path will be continued to wipers 220 and 221 as before, and to conductors 268 and 269 respectively. /2

Assume that the calling party sent digit 71 :from the calling device 73 by design after initiating-the call. Of course, the functioning of theselector inv4 Fig. 1 will be as described when one open impulse was inadvertently introduced as set forth. If the calling party now sends digit 9" from the calling device 73, Fig. 2 will function in a manner as before described, only in this instance the shaft will be stepped up so the wipers register in line with the ninth bank level. Further, the operation' is the same so far as the wipers automatically rotating-in after the cessation of the vertical stepping. However, upon wipers 218,1219, 220 and 221 'engaging bank contacts 270. 271, 272 and 273^respectively a modified functioning transpires' It will be noted bank contacts 270, 272l and 273 are dead and bank contact 271 is permanently grounded.

When wiper 219 rotates toward bank contact 271 relay D2 will' actuate because the ground-l short-path does -not exist after relay E2 deactuates; the selector technically seizing in the manner as beforeset forth. At the same juncture a circuit path is completed from grounded bank contact 271-, wiper 219armature 258, resting contact 274' to the winding of' relay F2, causing it to actuate and lockfrom grounded working contact208, armature 209, working contact 210, conductor 275, armature 276 to working contact 277. Also a ground path now exists from the grounded'conductor 275, armature 278, working contact 279', armature 280, resting contact 281, contacts 262-263 to the release magnet, causing-it to actuate and restore the shaft to normal position.

Incidental to relay D2 actuating relay A2 will deactuate. Also," incidental to the shaft restoring, contacts 229-230 will open, deenergizing re lay D2, causing it to deactuate.

Relay B2 will remain actuated until relay D2 deactuates andreenergizes relay A2, so no lapse of ground occurs to conductors 275 and 212. Upon the shaft reaching normal,- contacts 282 and 283 reengage, closing 'a circuit from the grounded armature 276, working contact 284, conductor 285, contacts 282-283,'conductor 254 to the winding of relay G2, causing it to actuate andlock-from thegrounded conductor 285, arma--I ture 286 to working contact 287. Relays A2, B2, F2 and G2 are now actuated.

It will be vnoted that the grounded armatur 256 is now fre'efrom'resting contact 257 and applied to working' contact 251 attached to common conductor- 250.- Also, wipers 218 and 219 step into engagement with the second bank contact set. The sai'dsecond bank contact engaged by wiper 219 is free from ground because conductor 252 is un'grounded, so it will have no operative eil'ect. 'Ihe bank contact engaged by wiper 218 is assumed ungrounded so the selector Fig. 2 will seize in a manner as, before set forth, continuingjthe telephonie path from wipers 220 and 221 to conductors 289 and290 respectively.I Had wiper 218'encountered ground potential on the said second bank contact engaged by it the selector would have advancedtwo steps to test the next trunk of the group. The ilrst bank position following (third) is guarded by ground potential received over conductor 250, as was the rst bank contact of the level as set forth. When the selector Fig. 2 seizes (on the fourth bank contact position) relay D2 will actuate, followed by the deactuation of relays B2, F2 and G2.

From the foregoing it is clear that if digit 7 were sent in lieu of digit 8 the same manner of functioning would take place on the seventh level as described for the eighth level.

Thus, if digit 0 is sent after Fig. 2 is seized the sets of trunks adapted to be normally seized on said level may be selected. If any digit from 1 t0 8 inclusive is sent after Fig. 2 is seized the sets of trunks adapted to be normally seized on said levels may be selected. So the trunks of the various levels need not correspond in multiple relation as to different levels, though the first (and alternate) trunks of the levels from 1 to 8 inclusive are so tied to a common switchboard equipment, Fig. 3. However, if digit 9 is sent following the seizure of Fig. 2 the said digit will be obliterated and thereafter the trunks adapted to be normally seized are non-seizable, but alternate sets of trunks which were normally nonseizable are now seizable.

If the calling party hangs his receiver on the hookswitch following the seizure of Fig. 2 in any of the described conditions assumed,V a period exists from the deactuation of relay B2 until the shaft is normal when the said selector Fig. 2 is unguarded, and therefore seizable, though it is not normal. The release magnet R.. M. 2 has an auxiliary armature 292 which engages working contact 293 when the said R. M. 2 actuates. Due to the said R. M. 2 being slugged the said contact will remain engaged until the shaft restores. While the said contacts are closed a ground path exists from grounded springs 294-295, contact 293, armature 292 to conductor 212, thus guarding the selector until complete normal is attained.

The selector Fig. 2 has wide uses in the art other than exampled. For example, another use is as a first selector, and when so used in a multioflice exchange'it will function as a rst selector and also as a local second selector, thus obviating the installation of specific local second selectors.

With reference to the meter shown in Fig. 1, the electro-magnet of the meter device is connected from the middle spring of the cam spring set. When the wipers on the switch shaft rotate oif the last bank terminal set of a level the said middle cam spring will be flexed into engagement with spring 29, disengaging spring 30. This placesfthe winding of the meter magnet in series with the calling telephone and the windings of the line relay A, operating the meter to register the attempt to seize a trunk of the level when all are busy, the calling party perceiving the busy tone applied through the winding of the electro-magnet.

I claimz- 1. A selector having levels of bank contacts and a single set of wipers, said contacts terminating in outgoing trunks corresponding to a plurality of trunk groups, an auxiliary Wiper carried by the shaft of said selector which is adapted to engage a contact corresponding to one of said levels corresponding to a first trunk group, a release circuit. said contact completing the release circuit for the purpose of restoring said shaft to normal position and incidentally adapt the same wipers of said selector to electrically register with outgoing trunk contacts of a second trunk group.

2. In a telephone system, a coordinate movement wiper selective switch with levels of bank contacts, each level containing two trunk groups engaged by the same wipers, means for operating the wipers with selective respect to the two groups of a level, and means controlled by a movement of the wipers for determining the selection in a specific one of said two groups by grounding a contact companion to the group not to be selected.

3. In a telephone system, a selective switch, said selective switch having a directed primary movement and an automatically applied secondary movement responsive to the primary movement, two groups of trunks of a level, automatically applied means for testing for an idle trunk in only one or the other of the two groups of trunks of the level by the same wiper responsive to a directed primary movement of the wiper, and directively controlled automatic means for at will barring one or the other said group from the test.

4. A selective switch with levels each having sets of bank contacts connected to two trunk groups respectively, auxiliary private bank contacts individual to each set of bank contacts in multiple relation in two groups corresponding to the trunk groups terminating in said bank 105 contact sets, and means for independently grounding all of the contacts of any of the said groups of auxiliary private bank contacts for the purpose of preventing connection to be made to the bank contact sets companion to the rell I spective private bank contacts of the auxiliary private bank set grounded.

5. A selective switch having a plurality of bank levels, each said level having a plurality of sets of line and private contacts, an auxiliary private bank contact for each set, the sets being divided into a plurality of groups, and means including the auxiliary private bank contacts of a respective group for barring all the sets of contacts of its group from seizure resultant to a single operation.

6. In a telephone system, an automatic selector switch having directively controlled primary movement for simultaneously selecting groups of lines and automatic secondary movement to select an idle line inthe selected groups, means for causing the primary movement of said switch and for initiating the secondary movement. means for continuing the secondary movement whether all the lines in the groups selected in the primary movement are busy or not and means directively operated before the selection of the groups has been initiated for determining whether such said continued secondary movement is to be effected.

7. In a telephone system, a selective switch for common connection with two groups of trunks respectively which groups can be alternatively barred against seizure, one of said groups being normally unbarred and the other said group being normally barred, means for operating the wiper set into simultaneous selective relation to the groups, automatically applied means to selectively test only the trunks of the unbarred said group consequent to the selection of the groups, means associated with the trunk groups for barring them against seizure respectively, and directively controlled automatic means for operating the third said means.

8. In a telephone system, a selective switch, a

iplurality of groups of trunks, a common wiper after selectively operating the wiper from normal to connect the selector with a trunk oi' the said one group. Y

9. In a telephone system, a selective switch for connection with a plurality of groups of common trunks, a single set of connecting terminals ci the selective switch, one of said groups being normally unbarred to seizure by the terminals and the other of said groups being normally barred against seizure by the terminals. means for operating the terminals of the selective switch to seize a trunk of only the unbarred group, vmeans eii'ective from a preliminary operation and restoration of the said terminals oi the selective switch for barring the said unbarred group and for unbarring the said barred group to the said terminals, and means for thereafter operating said terminals to seize a trunk o! the said normally barred group.

10. In a telephone system, a selective switch for connection with two groups of trunks, another selector for connection to the said groups -of trunks, one o1' said groups being normally barred against seizure only by the first said selective switch, means associated with said one trunk group for baning the ilrst said selective switch from seizing a trunk thereof, means in the first said selective switch for operating the iirst said means to unbar the said one group, and means for operating the second said selective switch with selective and testing relation to either of the groups to seize a trunk thereof regardless of the condition of the iirst and second said means.

11. In a telephone system, an automatic switch having directively controlled primary movement i'or selecting groups of lines and a secondary movement thereafter wherein the groups of lines can be selectively tested and an idle unbarred tested line thereof seized, means for causing the movements of theswitch to select and `test for an idle unbarred line to seize, directively controlled means for barring certain of the lines while idle, and means for thereafter operating the switch with selective relation to the groups to seize only an idle unbarred line tested regardless of barred idle lines tested.

12. In a telephone system, an automatic switch having directively controlled primary movement for selecting groups of lines and a secondary movement thereafter wherein the groups o1' lines can be selectively tested and an idle unbarred line seized, means for causing the movements of the switch, directively controlled means for barring certain of the lines, and means for thereafter directively operating the switch to selectively test the said certain lines and ignore the said certain lines tested regardless oi their busy or idle state.

13. In a telephone system, a two dimension selective switch having a single set of wipers with levels of bank contacts commonly swept by the set of wipers wherein two groups of trunks lead from the same level, means for operating the set of wipers in a rst one of said dimensions to select the said level, automatically applied means for initiating and continuing the automatic secondary movement thereof in the vsaid groups,

other said dimension with selective relation to and means for causing the switch to diiierentiate in operation in accordance with thetindividual groups of the level selectively atec d.

14. In an automatic telephone system, a two dimension selective switch wherein two groups of trunks lead from the same level thereoiI and are engaged commonlyby the same wiper set, means for operating the wipers in one said dimension for setting the wipers of the set in hunting relation in the other said dimension with respect to the level responsive to a single directive operation, and directively controlled automatic means for barring a specific one of said;

groups oi the hunted level against seizure regardless of the busy or idle state oi' the trunks of the said one group.

15. In an automatic telephone system, a selective switch having two groups oi' trunks leading from the same level engaged by a common wiper set, only one said group being normally barred against seizure by the wiper set regardless of the idle or busy state of its trunks, directively controlled automatic means for operating the wiper set in a predetermined prelimiary step, automatically applied means for thereupon initiating the testing of both the barred group and the unbarred group by the wiper set, means for preventing the seizure of a trunk o1' i ebarred group regardless of the idle or busy state o1 any of the trunks thereof, and directively controlled automatic means responsive to an alternative preliminary step of the wiper set for unbarring the said barred group and for barring the said normally unbarred group against seizure by the wiper set.

16. In an automatictelephone system, a selective switch `having two groups of trunks leading from the same level engaged by a common wiper set, the trunks oi' one set being normally barred and the trunks of the other set being normally unbarred against seizure by the wiperv set, an auxiliary relay, means for operating the wiper set into hunting relation with respect to both said groups by one operation oi the wiper set from normal position, and automatically directed means including the relay i'or unbarring the previously barred group and barring the previously unbarred group before the hunting takes place.

l?. In a telephone system, a selective switch, said selective switch having a directed primary movement and an automatic secondary move-,

ment consequent to the primary movement, two groups oi' trunks subject to automatic test by the same wipers of the selective switch during the secondary movement, and means whereby one or the other said group will be barred from the test depending upon Iii a specic preliminary movement and restoration oi' the vor has not occurred.

selective switch has 18. In a telephone system, a selective switch,

bank contact positions commonly accessible from a set of wipers of the selective switch, groups of trunks leading to random vbank contact positions, and auxiliary bank contact position, and means dependent upon iirst directively setting the selective switch with relation to the said auxiliary position for determining which said group will be subject to seizure.'

19. In a telephone system, a selective switch,

said selective switch having a directed preliminary movement and a primary movement thereafter to set the selector into selective relation to a group oi' trunks, and an automatic secondary movement consequent to the said primary movement to test the individual 4trunks of the group selected, a wiper set of the selective switch, bank contacts in sets commonly accessible from the said wiper set, groups of trunks leading from promiscuous said bank contact sets, means for operating the wiper set into individual testing relation to the respective trunks of one or the other said groups alternatively, and means dependent upon first operating the wipers in the preliminary movement for barring the unbarred group against individual` test and unbarring the trunks of the other said trunk group for individual test.

20. In an automatic telephone system, a calling line, an impulse contact for the calling line, a selective switch, a set of wipers of the selector having fixed positions with relation to each other, sets of bank contacts belonging to two groups of trunks, means controlled over the calling line by the impulse contact for thereupon causing the wipers of the selective switch to hunt over both the said trunk groups, means controlled over the calling line by the impulse contact before initiating the hunting operation for moving the said set of wipers in a predetermined manner, and means responsive to said movement for thereafter barring the trunks of a predetermined said trunk group hunted over from being seized by the said set of wipers.

21. In a telephone system, an automatic selective switch, a level of bank contact sets, a set of movable terminals of the switch for cooperation with corresponding contacts of the respective bank contact sets, automatic means for operating the said terminals into engagement with a specific set of said bank contact sets, automatically applied means for thereupon moving the said terminals from the engaged bank contact set only if the engaged bank contact set is busy, and directively controlled automatic means for determining if the movable terminals will effect the said movement from the engaged bank contact set regardless of the busy or idle state of the said engaged bank contact set.

22. In an automatic telephone system, a selective switch, two groups of lines leading from a level thereof, a busy test guard contact for each of the lines, an auxiliary bar contact for each line of one said group, a set of wipers permanently positioned with respect to each other coincidently cooperative with the said contacts of the lines of said one group respectively, a relay, an armature of said relay for placing a bar potential on the bar contacts of the lines of said one group, means for operating the set of wipers into hunting relation to the level, means for hunting over the lines of the two groups of the level with the wiper set to seize the first line not guarded by its busy test contact nor barred by a said bar contact, means for operating the wiper set to operate the armature of the relay, means responsive to the operation of the said armature to place the bar potential on the said bar contacts, and means thereafter operative for causing the wipers to pass over the busy test contacts of the said one group regardless of their busy or idle state.

23. In a telephone system, an automatic selective switch, a set of testing wipers of the selector having a mutually permanent relation to each other, means for testing the busy and barred condition of the respective lines of two groups, another selective switch for connection to said groups of lines, means companion to one said line group for barring the first said selective switch from seizing a line of only said one line group regardless of the busy or idle state of the lines of the group, automatic means responsive to the directed operation of the wiper set for operating the second said means, and means for operating the second said selector with selective and testing relation to the said groups to seize a line thereof regardless of the condition of the second said means.

24. In a telephone system, an automatic selective switch, a set of testing wipers of the selector having a mutually permanent relation to each other, means for testing the busy and barred condition of the respective lines of a plurality of groups, another selective switch for connection to said groups of lines, means companion to one said line group for barring the first said selective switch from seizing a line of said one line group regardless of the busy or idle state of the lines of the group, automatic means responsive to the directed operation of the wiper set for operating the second said means, and means for operating the second said selective switch with selective and testing relation to the said groups to seize a line thereof regardless of the condition of the second said means.

25. In a telephone exchange system, a rotary selector switch having a terminal bank, groups of trunks connected to said bank and having their terminals arranged in an interposed relation, another terminal of said bank being allotted for the selection of a particular group, and means for moving the switch over the terminal allotted for group selection and also terminals of a nonselected group in selecting an idle trunk in a selected group.

26. In a telephone exchange system, a selector switch having a terminal bank, groups of trunks connected to said bank and having their terminals interspersed, another terminal of said bank being allotted for group selection, and means for initially moving said switch onto the latter terminal to select a group and then moving the same over terminals of another group in selecting an idle trunk in the selected group. 27. In a telephone exchange system, a selector switch having a terminal bank, groups of trunks connected to certain terminals of said bank, test terminals for said groups, electro-magnetic means assigned to the groups, means for energizing said electro-magnetic means to place a certain electrical condition upon the terminals of the groups of trunks associated therewith, and means for moving said switch over other test terminals of said groups until a terminal is found having the same electrical condition as the rst named test terminals of said groups.

28. In a telephone exchange system, a selector switch having a terminal bank, groups of trunks connected to certain terminals of said bank, another terminal being allotted for group selection, test terminals for said groups, means for selecting saidanother terminal, means operated thereupon yto place a certain electrical condition upon test terminals of the selected group, and means for moving the switch over said another terminal and terminals of the selected group in selecting an idle trunk therein.

29. In a telephone exchange system, a selector switch having a terminal bank, groups of trunks connected to certain terminals of said bank and having their terminals interspersed, another terminal of said bank being allotted for group selection, test terminals for said groups, means for selecting said another terminal, means operated thereupon to place a certain electrical condition upon test terminals of the selected group, and means for moving the switch to hunt an idle trunk in the selected group, the test for said idle trunk being determined by the iinding of another test terminal having the same electrical condition as the test terminals of the selected group.

30. In a telephone exchange system, a telephone line, a selector switch for extending said line and having test brushes, groups of trunks served by said switch, means for operating said switch to select a group of trunks, electromagnetic means associated with the groups of trunks and energized upon the selection of a group thereof to place a certain electrical condition upon the terminals of a said group, and means for operating the switch tohunt an idle trunk in the selected group, the seizure of a trunk depending upon the test brushes simultaneously engaging terminals having said certain electrical condition.

31. In a telephone exchange system, a telephone line, a rotary selector switch for extending said line and having test brushes, groups of trunks served by said switch and having their terminals interspersed, a stepping magnet operable to step said switch to select a group of trunks, a relay associated with a said group of trunks and energized upon the selection thereof to place a certain electrical condition upon the terminals of the selected group with which one of said test brushes is associated, and means for continuing the operation of said stepping magnet until the other test t brush engages an associated terminal having the same electrical condition as that applied to the last named terminal.

32. In a telephone exchange system, calling and called substation lines, switching means for extending a call from the calling substation line, a selector switch for connecting the calling line to the called line and including a terminal bank,

.groups of trunks connected to certain terminals of the said bank, another terminal being allotted for group selection, and directively controlled means moved over said other terminal and also terminals of a said group in selecting an idle trunk 'in the selected group leading to the said called substation line.

33. In a telephone system, a calling line, an automatic two dimension selective switch having a plurality of trunk terminal levels, a single set of movable wipers of the switch, groups of trunks terminating in a said level the respective trunks commonly accessible through the set of wipers, means whereby all the wipers of the set have access to all the trunks of said groups, a manually operated calling device on the calling line for directing the operation of the wipers of the switch in one said dimension to select a said level and then automatically in theother said dimension responsive to selecting the level to connect the calling line by the switch in talking relation with ya. trunk of a desired random said group, and

means whereby depending upon into which said ygroup of trunks in said level the calling line is to be connected with will determine how many manual operations of the calling device will be n required to eilect the said connection.

34. In a telephone system, a calling line, an automatic selective switch, a single set of movable wipers of the switch, the said wipers having a directed primary movement and a hunting movement thereupon responsive to all primary movements, called lines directly commonly accessible through the set of wipers, means whereby all the wipers of the set have access to all the trunks of said groups, a manually operated calling device onthe calling line for directing the operation of the wipers of the switch to connect the calling line by the switch in talking relation with a random called one of said called lines, and means whereby depending upon which said one of said called lines the calling line is to be connected to will determine how many manual operations of the calling device will be required tobeifect the said connection.

35. In a telephone system, an automatic switch, a single set of wipers of the switch, a plurality of groups of trunks in a single level of the switch commonly accessible from said set of wipers in the same plane of movement for talking connection thereto by .the switch, means whereby all the wipers of the set have access to all the trunks of said groups, a bar contact, and means whereby flrst automatically directing the wipers upon the bar contact will determine which sole group of said level can thereafter be connected with by said wipers of the switch. l

36. In a telephone system, a calling line, an

automatic switch terminating the calling line, a

group of lines accessible from the switch, a. movable terminal of the switch for testing the state of said lines one after another, `a meter, an energizing circuit contact set apart from the movable terminal closed for operating the meter, and

a cam for mechanically closing said contact set responsive to the movable terminal testing all the lines of the group and nding them busy.

37. In a telephone system, an automatic switch,

trunk lines lleading from said switch divided into transmitting a plurality of series of'impulses to said switch to cause all of the wipers of said set of wipers to select a subgroup in another of said main groups.

38. In a telephone system, an automatic switch, a single set of movable connective terminals for the switch, a plurality of groups of trunks, a set of fixed connective terminals for the respective individual said trunks, the terminals 'of each said iixed terminal set commonly accessible from the respective terminals of said set of movable connective terminals, a leading-in line foil the switch, an impulse sending device on the leadingin line for sending successive series of impulses lwhereineach series consists of one or more impulses constituting a single directive effort applied to the automatic switch, and means depending upon what said group of trunks is to be selected for determining how many said series must be sent tocompletely select the desired said group by the set of movable connective terminals.

39. In a telephone system, an automatic switch, a single set of movable connective terminals for the switch, aplurality of groups of trunks, a set of xed connective terminals for the respective individual said trunks, the terminals of each said xed terminal set commonly accessible from the respective terminals of said set of movable connective terminals, a leading-in line forA the switch, an impulse sending device on the leading-in line for sending successive series of impulseswherein each series consists of one or more impulses constituting a single directive effort applied to the automatic switch to move said set of movable groups by cmnectlve terminals from its normal resting position, means depending upon what said group of trunks is to be selected for determining how many said series nl ust be setto completely select the desired said group bythe set of movable connective terminals, and means whereby only when more than one set of impulses are required for selecting a desired group the movable connective terminals will be restored to normal resting position responsive to one of said series sent 'and then again operated to select the desired group from said normal resting position responsive to another one of said series sent.

40. In a telephone system, an automatic switch, a single set of movable connective terminals for the switch, a plurality of groups of lines, a set of xed connective terminals for the respective individual said lines, the terminals of each said xed terminal set commonly accessible from the respective terminals of said set of movable connective terminals, a leading-in line for the switch, an impulse sending device on the leading-in line for sending successive series of impulses wherein each series consists of one or more impulses constituting a single directive effort applied to the automatic switch to move said set of movable connective terminals from its normal resting position, means depending upon what said group of lines is to be selected for determining whether or not the said set of movable connective terminals will make only forward-acting movement from its normal resting position or must make retroacting movement from the position assumed by said forward-acting movement towards its normal resting positionbefore it can be thereafter selectively set upony the fixed terminals of a line of a desired said group.

41. In a telephone system, a multiple level automatic switch having a directed primary movement to select a level of sets of fixed connective line terminals for said lines and an automatic secondary hunting operation along the selected level to select the set of connective terminals of a corresponding line of the selected level following the said primary movement, a set of said connective terminals for the individual said lines, a single set of movable connective terminals for the switch, the terminals of said xed connective terminal sets commonly accessible from the respective terminals of said set of movable connective terminals, a leading-in line for the switch,

an impulse sending device on the leading-n line for sending successive series of one or more impulses wherein each series constitutes a single directive effort applied to the automatic switch, and means depending upon what level of lines is to be hunted along for determining whether or not said hunting operation will ensue responsive to the rst said series sent or only ensue responsive to a said series succeeding said first series.

42. In a telephone system, an automatic switch having a directed primary movement to select a group of sets of fixed connective line terminals for said lines and an automatic secondary hunting operation along the selected group of said sets to select the set of connective terminals of a corresponding line of the selected group following the said` primary movement, a set of said connective terminals for the individual said lines, a single set of movable connective terminals for the switch, the terminals of said fixed connective terminal sets commonly accessible from the respective terminals of said set of movable connective terminals, a leading-in line for the switch, an impulse sending device on the leading-in line a single set of movable connective terminals forv the switch, a plurality of groups of trunks, a set of xed connective terminals for the respective individual said trunks, the terminals of each said xed terminal set commonly accessible from the respective terminals of said set of movable con.

nective terminals, a leading-in line for the switch, an impulse sending device on the leading-in line for sending successive series of impulses wherein each series consists of one or more impulses constituting a single directive effort applied to the automatic switch, and means depending upon what said group of trunks is to be selected for determining whether the flrst said series sent will complete the directive selection of the group or whether a succeeding series to said rst series sent must be sent following said first series sent to complete'the directive selection of the group.

44. In a telephone system, a directively operated automatic switch, a single set of movable selective terminals for the switch, a plurality of groups of trunks, terminals for the respective trunks commonly accessible from the respective said movable terminals, and means whereby when the said set of movable terminals is operated to select a certain one of said trunks the said set of movable terminals must rst be operatively moved from the normal resting position and then restored from said operated position before the said set of movable terminals can be thereafter moved to select the said desired trunk.

45. In a telephone system, a directively operated automatic switch, a single set of movable selective terminals for the switch, a plurality of groups of trunks, terminals for the respective trunks commonly accessible from the respective said movable terminals, means whereby when the said set of movable terminals is operated to select a certain one of said trunks the said set of movable terminals must rst be operatively moved from the normal resting posit-ion and then restored from said operated position before the said set of movable terminals can be thereafter moved to select the said desired trunk, and means whereby certain other of said trunks can be selected without rst restoring the said set of terminals from said operated position.

46. In a telephone system, means including a plurality of serially related directively controlled automatic switches for connecting a calling and a called subscribers line, said plurality of switches including a rst selector having a single set of wipers, a different and lesser pluralityof similar switches for connecting the said calling line with another called line, a uniform numbering system in which all of the said subscribers have the same number of digits in their telephone numbers, and means in the first selector used in calling the said second called line for canceling one of the digits in the number thereof.

47. In a telephone system, means including a plurality of serially related directively controlled automatic switches for connecting a calling and a called line, said series including a plurality of `including a smaller number of selectors than said irst series, a uniform numberingsystem in which all of the said 'subscribers have the same number of digits in their telephone numbers, and means in one of the selectors used in calling the sa1d second called line for canceling one of the digitsv in the number thereof.

48. In a telephone system, a switch having a wiper, levels of trunk line terminals of two numerical orders accessiblefrom the said wiper, means for operating the switch in corrrespondence with the numerical orders, respectively, to select a trunk line of a corresponding numerical order level, and means for barring the switch from seizing a trunk of a selected level of one of said numerical orders if the switch has been selectively operated with respect to such level in accordance with the other numerical order.

49. In a telephone system, a switch, a group of trunks accessible to the wipers of said switch and extending to thousands selectors, a second group of trunk lines accessible to said switch via the same wipers and extending to hundreds selectors, means'for operating the switch in accordance with the thousands and hundreds digits of telephone numbers to select said groups, respectively,- and means effective to prevent the seizure of a trunk line in case said switch is operated to select the group of trunk lines leading to hundreds selectors responsive to the thousands digit of a number.

50. In a multi-oilce telephone system, a calling line of a first oilice, a called Iline of said first oilce, a called line of another of said olces, a first switch terminating the calling line, a single set of movable link Wiper terminals of first said switcha plurality of corresponding sets of fixed.

trunk terminals cooperative with said movable terminals, a trunk termin-ating in each said set of said fixed terminals, means for employing each said movable terminal set in like manner for all call extensions effected by said switch to a trunk through a said set of fixed terminals, other switches each terminating a respective said trunk, a calling device on the calling line, means responsive to successive manual operations of the calling device to send a train constituted of a plurality of series of impulses the said plurality numerically corresponding to the number of said manual operations, means for causing said impulses to be directly effective -to said first switch and certain of said switches for extending a trunk connection from the calling line to either of said called lines, means so a like number of said series will be required to link a said trunk connection from the calling line through said first switch to either of said calling lines, and means depending upon to which said called lines the connection is to be extended for determining whether one or a plurality of said series will be required to completely operatev said first switch to eect a connection through said movable terminals to a sai dset of trunk terminals towards said line ca e 51. In a telephone system, a main exchange and abranch exchange, an automatic switch, a set of wipers of the switch having a motion in two intersecting planes, trunk lines leading from said switch to each exchange, means for operating said set of wipers in one plane in response to only the flrst digit of a called number to cause said set of wipers to select and connect to trunks to the main exchange and for operating said set of wipers in the same plane in response to the ilrst and second digits of a called number to cause all the specific wipers to select and connect to a trunk to the branch exchange, said iirst digit in the second instance causing said set of wipers to advance and then release before the second digit is called.

52. In a telephone system, a switch having a wiper, levels of trunk line terminals of two numerical orders accessible from the said wiper, means for operating the switch in correspondence with the numerical orders, respectively, to select a trunk line of a corresponding numerical order level, and means for preventing the connection being extended from a trunk of a selected level of one of said numerical orders if the switch has been selectively operated with respect to such level in accordance with the other numerical order.A

53. In a telephone system, a first and a second exchange, an automatic switch, a single set of wipers of the switch having a motion in two intersecting planes, trunk lines leading from said switch for each exchange, means for operating said set of wipers in one plane in response to only the rst digit of a called number to cause said set of wipers to select and connect to trunks for one of said exchanges and for operating the said set of wipers in the same plane in response to a plurality of digits of a called number to cause all the specific wipers to select and connect to a trunk for another of said exchanges, said set of wipers in the last said operation rst operating in said one plane and thereafter restoring to normal resting position before selecting and connecting to a trunk for said another exchange.

54. In a telephone system, afirst and a second exchange, an automatic switch, a single set of wipers of the switch having a motion in two intersecting planes, trunk lines leading from said switch for each exchange, means for operating said set of wipers in one plane in response to only the first digit of a called number to cause said set of wipers to select and connect to trunks for one of said exchanges and for operating the said set of wipers in the same plane in response to a plurality of digits of a called number to cause all the specific wipers to said set of wipers in the last said operation first operating in said one plane and thereafter retracting from the operated position before selecting and connecting to a trunk for said another exchange.

HERBERT M. FRIENDLY, 

